Unsaturated fats can help to lower cholesterol. They can be found in fruits and vegetables, nuts and seeds, oily fish and olive oil.

Uric acid is a chemical created when the body breaks down substances called purines. Purines are found in some foods and drinks including liver, anchovies, mackerel, dried beans and beer.

What it does: Needed for healthy skin, inside and out, protecting against infections. Antioxidant and immune system booster. Protects against many forms of cancer. Essential for night vision.

Deficiency Signs: Mouth ulcers, poor night vision, acne, frequent colds or infections, dry flaky skin, dandruff, thrush or cystitis, diarrhoea.

Best food sources: Liver, carrots, watercress, cabbage, squash, sweet potatoes, melon, pumpkin, mangoes, tomatoes, broccoli, apricots, papayas, tangerines.

What it does: Essential for energy production, brain function and digestion. Helps the body make use of protein.

Deficiency Signs: Tender muscles, eye pains, irritability, poor concentration, prickly legs, poor memory, stomach pains, constipation, tingling hands, rapid heartbeat.

Best food sources: Watercress, squash, courgette, lamb, asparagus, mushrooms, peas, lettuce, peppers, cauliflower, cabbage, tomatoes, Brussels sprouts, beans.

What it does: Needed for making use of protein. Helps the blood carry oxygen, hence essential for energy. Needed to make new cells. Essential for nerves.

Deficiency Signs: Poor hair condition, eczema or dermatitis, mouth over-sensitive to heat or cold, irritability, anxiety or tension, lack of energy, constipation, tender or sore muscles, pale skin.

Best food sources: Oysters, sardines, tuna, lamb, eggs, shrimp, cottage cheese, milk, turkey, chicken, cheese.

What it does: Helps turn fats, sugars and protein into energy. Needed to repair and maintain healthy skin, inside and out. Helps to regulate body acidity. Important for hair, nails and eyes.

Deficiency Signs: Burning or gritty eyes, sensitivity to bright lights, sore tongue, cataracts, dull or oily hair, eczema or dermatitis, split nails, cracked lips.

Best food sources: Mushrooms, watercress, cabbage, asparagus, broccoli, pumpkin, beansprouts, mackerel, milk, bamboo shoots, tomatoes, wheatgerm.

What it does: Essential for energy production, brain function and the skin. Helps balance blood sugar and lower cholesterol levels. Also involved in inflammation and digestion.

Deficiency Signs: Lack of energy, diarrhoea, insomnia, headaches or migraines, poor memory, anxiety or tension, depression, irritability, bleeding or tender gums, acne, eczema or dermatitis.

Best food sources: Mushrooms, tuna, chicken, salmon, asparagus, cabbage, lamb, mackerel, turkey, tomatoes, courgettes, squash, cauliflower, wholewheat.

What it does: Involved in energy production, controls fat metabolism. Essential for brain and nerves. Helps make anti-stress hormones. Maintains healthy skin and hair.

Deficiency Signs: Muscle tremors or cramps, apathy, poor concentration, burning feet or tender heels, nausea or vomiting, lack of energy, exhaustion after light exercise, anxiety or tension, teeth grinding.

Best food sources: Mushrooms, watercress, broccoli, alfalfa sprouts, peas, lentils, tomatoes, cabbage, celery, strawberries, eggs, squash, avocados, wholewheat.

What it does: Essential for protein digestion and utilisation, brain function and hormone production. Helps balance sex hormones, hence use in PMS and the menopause. Natural anti-depressant and diuretic. Helps control allergic reactions.

Deficiency Signs: Infrequent dream recall, water retention, tingling hands, depression or nervousness, irritability, muscle tremors or cramps, lack of energy, flaky skin.

Best food sources: Watercress, cauliflower, cabbage, peppers, bananas, squash, broccoli, asparagus, lentils, red kidney beans, Brussels sprouts, onions, seeds and nuts.

What it does: Strengthens immune system – fights infections. Makes collagen, keeping bones, skin and joints firm and strong. Antioxidant, detoxifying pollutants and protecting against cancer and heart disease. Helps make anti-stress hormones, and turns food into energy.

Deficiency Signs: Frequent colds, lack of energy, frequent infections, bleeding or tender gums, easy bruising, nose bleeds, slow wound healing, red pimples on skin.

Best food sources: Peppers, watercress, cabbage, broccoli, cauliflower, strawberries, lemons, kiwi fruit, peas, melons, oranges, grapefruit, limes, tomatoes.

What it does: Helps maintain strong and healthy bones by retaining calcium.

Deficiency Signs: Joint pain or stiffness, backache, tooth decay, muscle cramps, hair loss.

Best food sources: Herrings, mackerel, salmon, oysters, cottage cheese, eggs.

What it does: Acts as an antioxidant, protecting cells from damage, including against cancer. Helps body use oxygen, preventing blood clots, thrombosis, atherosclerosis. Improves wound healing and fertility. Good for the skin.

Deficiency Signs: Lack of sex drive, exhaustion after light exercise, easy bruising, slow wound healing, varicose veins, loss of muscle tone, infertility.

Best food sources: Unrefined corn oils, sunflower seeds, peanuts, sesame seeds, beans, peas, wheatgerm, tuna, sardines, salmon, sweet potatoes.

What it does: Blood clotting.

Deficiency Signs: Symptoms include those of a purpuric syndrome, i.e., ecchymosis, petechiae, bruising, abdominal pain, risk of massive bleeding, cartilage calcification and severe malformation of bone development and calcium deposits in blood vessels. In children, this can cause alterations in the face, nose, bones and fingers.

Best food sources: Cauliflower, Brussels sprouts, lettuce, cabbage, beans, broccoli, peas, watercress, asparagus, potatoes, corn oil, tomatoes, milk.